JAPANESE WATER PEPPER SEEDS

Polygonum hydropiper var. fastigiastum

Common water pepper is an annual weed of damp places throughout much of the northern hemisphere. It has been employed as a medicinal for thousands of years in diverse cultures and modalities, and as a culinary herb to a lesser extent, often as a substitute for black pepper owing to its similarly pleasant pungency. This specific selection is culitivated for culinary use in Japan and produces plants with superior flavor and fantastic color.

Most frequently encountered in the form of dark red microgreens, known as akatade, alongside sashimi. The flavor of these tiny sprouts is wonderfully herbaceous and pungent and probably “hot" to some, but the heat does not linger. Leaves of the mature plants are used to produce tadezu, commonly used with ayu, or sweetfish. Curiously, the tradition of eating water pepper and shiso along with sashimi may have to do with protection from foodborne pathogens. Water pepper leaves contains polygodial, a biologically active compound that is powerfully antiparasitic and antimicrobial. Shiso leaves contain perillaldehyde, a unique monoterpenoid that enhances the effect of polygodial by four fold. Coincidence?

Both leaves and seeds of this species are employed as medicine in TCM. Though not exactly interchangeable, they are both effective at resolving damp stagnation, edema and toxicity. They are also astringent and potentially haemostatic. We recommend tincture of the fresh leaves, and saving the seeds for producing microgreens.

These seeds are viable for only a year or so and should be refrigerated until sown. Germination is sometimes slow and erratic but can be improved by soaking seeds before sowing, and refrigerating the sown seeds for a week before returning to room temperature in bright light to germinate in 2-4 weeks. Avoid excessive heat and do not freeze soaked seeds.

Though adapted to damp pondside soils, plants can be grown successfully in gardens given plenty of water and mulch. Pretty fragrant flowers rarely appear before autumn.

Packet contains at least 500 seeds.